Since the O-ring for the pump piston deteriorates and the pressure does not rise
I bought it for that exchange. I tried installing and pressurizing but I am satisfied because it seems to be close enough

Because the order was few, I was very thankful that I was able to place an order in units of 1 piece. As this kind of parts are many kinds, it takes a little effort to find the same thing from the dimensions of the part actual article, so I think that it will be convenient if it becomes possible to search by inner diameter, outer diameter, wire diameter, etc.